The organiser of a Black Lives Matter rally held in Londonderry at the weekend said she has no regrets and would do the same again despite facing prosecution.
Hundreds attended rallies held in Custom House Square in Belfast, where police issued a total of 15 fines, and in Guildhall Square, where 57 people were fined.
Some said they will refuse to pay up.
Following criticism of the PSNI operation, First Minister Arlene Foster backed the response as "proportionate".
However, Ciaran Moynagh, a solicitor from Phoenix Law -which offered free legal advice to protesters, questioned the difference between those gathering for a protest and those taking part in long queues for some shops.
Among those who received fines in Derry were Blathnaid O'Donnell and her mother Helen.
Explaining why neither she nor her mother intend to pay up, Ms O'Donnell said: "If I pay this fine it would be defeating the reason for me being at the rally in the first place. It would be as if I accepted that it was wrong to protest against the death of George Floyd.
I am going to do every thing that I can to continue fighting the injustice and not threat or intimidation will stop me from doing thatBlathnaid O'Donnell
"Civil Rights in Ireland was born in Derry and I am proud to be from this city and proud of everyone who was at the rally on Saturday and proud of everyone, who like my mother and I, are refusing to pay this ridiculous fine."
Lillian Seenoi Barr from the North West Immigrants Forum said organising the Derry rally was an essential part of the work her organisation does in supporting minority communities in the city.
She received a police caution which she described as "unfair".
"I accept coronavirus is a pandemic, but we provided gloves, masks and hand sanitiser but racism is also a health pandemic that is enshrined in our society," she said.
She added: "I am going to do every thing that I can to continue fighting the injustice and not threat or intimidation will stop me from doing that.
"Police issued fines at our rally but not at Benone Beach where I myself saw thousands of people and yet the police drove up the beach and back again and did not issue any fines.
"I have been cautioned by the PSNI who have forwarded my name to the PPS and recommended prosecution. It is unbelievable that the PSNI would criminalise those who came to the rallies and it was very, very unfair."
Assistant Chief Constable Alan Todd defended the PSNI actions, saying the message to stay away had been clear.
He explained: "In other times, we would have worked with the organisers and protesters to facilitate lawful and peaceful protests to mark the avoidable and unnecessary death of George Floyd, but these are not ordinary times.
"The Health Protection Regulations are in place to protect us all during this pandemic and it is everyone's responsibility to adhere to them to protect our society."
Mrs Foster said she considers the police operation on Saturday was a "proportionate reaction to the fact that regulations were being breached by those who had been asked by the executive members to find a different way to protest".
Deputy First Minister Michelle O'Neill said she had joined an online protest on Saturday in solidarity with the Black Lives Matter campaign.